Also found in: Dictionary, Thesaurus, Medical, Legal, Wikipedia.


Any mechanical device or chemical agent used to prevent conception.



one of various mechanical, biological, chemical, and surgical agents and methods used to prevent pregnancy and one of the most common forms of contraception.

Mechanical contraceptives principally prevent spermatozoa from penetrating into the uterus; they include female contraceptive devices that are inserted into the cervix and uterine cavity and male condoms. Chemical contraceptives act on spermatozoa that have entered the vagina by immobilizing them and depriving them of their fertilizing capacity. Some scientists regard synthetic preparations that have a general resorptive effect on the body to be chemical contraceptives. It is more accurate, however, to regard them as biological contraceptives. Agents of chemical contraception used locally include globules, suppositories, pastes, creams, tablets, and foams. They contain acids, quinine, and tannin and a contraceptive base. Combination contraceptives unite both chemical methods that are used locally and mechanical methods; they include chemical (melting) caps, sponges, tampons saturated with spermicides, and douches that spray the vagina with spermicides. Biological contraceptives act on various parts of the reproductive process, for example, on the movement of sex cells through the reproductive system, on fertilization, and on the implantation of a fertilized ovum in the uterus. Biological contraceptives include highly active synthetic hormonal preparations for oral administration and certain biologically active nonhormonal agents, such as antihyaluronidases and antihistamines. The effectiveness of biologically active nonhormonal agents has not yet been sufficiently proved.

Oral and intrauterine contraceptives are widespread. Oral contraceptives have various mechanisms of action. The majority of highly active synthetic hormonal preparations must be taken daily for 21 days starting on the fifth day of the menstrual cycle in order to be almost 100 percent effective. Oral contraceptives have been developed that are effective when taken after presumed fertilization. In many women these contraceptives may produce bloody discharge, vomiting, and nausea. These reactions, however, are usually temporary and do not necessitate discontinuing the preparations. Oral contraceptives must be used only under a physician’s supervision. It is not recommended that they be used for more than six months consecutively because of possible complications.

Intrauterine contraceptives come in various sizes and shapes, for instance, rings, loops, and spirals. They are made of various materials, such as stainless steel and polymers. Insertion is into the uterine cavity, where the contraceptive is left as long as one year. The mechanism of intrauterine contraceptives is not sufficiently clear. Menstrual cycle irregularities, pain, and inflammatory diseases sometimes occur with their use.

Prolonged use of any contraceptive is detrimental to health, and it is necessary to change the contraceptive periodically.


References in periodicals archive ?
The RACGP is an independent organisation and receives no funding from any contraceptive maker.
The rationale behind giving poor Filipino women free contraceptives is for 'family planning purposes.
The women who were given contraceptive pills estimated their quality of life to be significantly lower than those who were given placebos.
Data collection based on women's own response to survey questions in questionnaire schedule containing information about family, fertility profile, sociocultural data, and contraceptive use.
Medical eligibility criteria for contraceptive use, Fifth edition.
Enrollees in a health plan that excludes contraceptive coverage would have no recourse.
Male condoms are more popular than female condoms; thereby significantly boosting the growth of the overall contraceptive market.
However, they say few studies have investigated whether the use of hormonal contraceptives influences depression risk.
To estimate the percentage distribution of desired contraceptive methods that might be needed in Puerto Rico, data from the Contraceptive CHOICE project, which was designed to remove the financial barriers to contraception, offer all methods and emphasize the most effective methods of birth control, and reduce unintended pregnancy in the St.
Specifically, women who met their relatively more-attractive husbands while using hormonal contraceptives experienced a boost in marital satisfaction when they discontinued employing those contraceptives.
Bi-variate analysis was done to show relationships between current contraceptive use and all outcome variables mentioned before and multivariate logistic regression was employed to predict factors influencing contraceptive uptake.
Obesity increases the metabolic rate, increases clearance of hepatically metabolized drugs, increases circulating blood volume, and affects the absorption of contraceptive steroids through the adipose tissue, she said, so "the serum drug levels may be insufficient to maintain contraceptive effects, but the data are very limited.